Propeller



Jan. 24, 1933.

E. G. KQNTos PROPELLER Filed Jan. 23, 1951 Patented Jan. 24, 1933 UNITED STATES PA'rENr OFFICE EMMANUEL G. KONTOS, F CHICAGO,

' rnorELLEn Application led January 23, 1931. Serial No. 510,663.

such conditions, and minlmize the possibility of such diving in other types of iiying machines.

Another object is to provide an improved propeller for flying machines or toys `with means to maintain said machine in its true course, without deviating therefrom, horizontally or vertically.

Anothermbject is to provide a. propeller with improved novelly shaped blades adapted for use on flying machines, helicopters, 4marine devices, fans, or ornaments.

Another object is 'to provide a propeller of the character referred to with means for ladjusting readily. the,k pitch of the blades.

The foregoingan'd such other objects of the invention as will appear hereinafter as Vthe description proceeds, will be more readily understood from a perusal of the following specification, reference being had to the accompanying drawing, in which:

Fig. 1 is a front elevational view of the l improved propeller.

Fig. 2 is a side elevational view.. Fig. 3 is a fragmentary enlarged sectional view, through the hub and one blade.

l F ig. 4 is a fragmentary view of a disc from which the propeller blades'are cut.

Fig. 5 is a perspective view of a modified form of hub cap.

' Fig. 6 is a fragmentary side elevational view of a modified form of blade.

, Fig. 7 is a fragmentary sectional view similar to Fig. 3, showing a modified form of blade.

Fig. 8 is a horizontal sectional view, taken on line 8-8 of Fig. 7.

The improved propeller is designed to re-v duce to a minimum, and in certain ,instances prevent, nose-diving of flying machines. The chief characteristics of the improved propeller reside in the novel shape and curvature 5,5

of the blades.

The blades 11 preferably are cut from a suitable disc 12, formed with va depressed central portion 13, and a downwardly turned circumferential portion 14. The edge of the downwardly turned circumference of the disc 12 preferably terminates above the plane of Vthe under side of the depressed central portion 13. As shown in Fig. 4 three improved substantially triangularly shaped blades are cut from each disc. 12.` l

The entering edgel of each blade is cut substantiall on a radial line on said disc, said cut being curved to conform substantially to a radial section of the disc. The

trailing edge 16 of each blade is cut along a curved line extending to the circumference of the disc tangentially from a small circular opening 17 at the center of said disc. `The circular opening 17 is provided to receive 75 the mounting hub of the propeller. The edge 16 also is curved similarly to the entering edge, whereby a blade is provided which increases in width, measured circumferentially, from ,the hub portion to the outer circumferential edge 14.

A. blade cut from such a disc in the manner described, curves forwardly in a radial plane from the relatively narrow inner end, or hub port-ion, to a diameter adjacent the circumferential edge, said edge being curved rearwrdly to provide an air pocket 20 in the rear s1 e.

When the improved blades are used on aeroplane propellers, it is preferable that only o two be employed, but more blades maybe provided particularly on propellers for use on helicopters, fans, ornaments, marine propellers, etc. Each blade preferably is ixedly .95

-justably mounted in the hub 21, whereby the pitch of the blades may be varied readily to suit various requirements.

The hub 21 is lixedly mounted upon a shaft 22 connected with asuitable source of power,

and hub caps 23, Apreferably in the form of ylcylindrical shells having their abutting edges held.

cut to correspond to the pitch of the blades which extend therebetween,'are placed one on each side of the hub 21, as shownfin Fig. 3. To change the pitch of the blades it is only necessary to remove the hub caps 23 and replace them with hub caps having their abutting faces pitched at the desired angle.l

In Fig. 5 a modied form of hub cap is illustrated, said cap having slotted angular openings 24 extending back-from the face 25, to receive the end of the hub portion of the blade. The angular disposition of slots 24 determines the The blade 26 illustratedin Fig. 6 is formed .-'substantially to conform to the curvature andfcontour of the wing of a sea-gull, or similar bird. This blade is substantially like the blade previously described, and may be employed successfully in every instance in which the other type of blade may be used.

"However, the pulling power of a propeller using this form of blade is slightly. less, due to the reduction in area.

In Figs. 7 and 8 a stream line propeller bladeis shown, said blade having its rear covering 27 cut from the curved disc 12, and its front covering 28 divergin from the tip toward thehub portion, and rom the trailing edge 16a toward the entering edge 15a.

-ential edge 14, the air pocketed behind the blades cannot slip, olf circumferentially.

Such circumferential slip of air as is common with known types of propellers reduces the pulling power of such "propellers By pocketing theair, it can escape only by the passing of the blade, whereupon said air slips off the trailing edge only of each blade.

The improved propeller, while rotating,

pitch at which the blades are ly curved circumferential edge, the entering edge of said blade being cut substantially on a radial line conforming' to a radial section f of said disc, and the trailing edge of said blade having a similar curvature.

v2. A substantially triangular propeller.

blade cut from a disc having a dished central portion and a downwardly curved circumfer-` ential edge, the entering edge of said blade being cut substantially on a radial line conforming to a radial section of said disc, and the trailing edge of said blade having a similar curvature.

3. A propeller blade cut from a disc having a dished central portion and a downwardly curved circumferential edge, said edge ending above the bottom plane of said dished portion, the entering edge of said blade being cut substantially on a radial line conforming to a radial section of said disc, and the trailing edge of said blade having. a' -similar curvature.

aol

' 4. A propeller-blade cut from a disc having a dished central portion and a downwardly turned circumferential edge, said edge terminating'av short distance from the bottom plane of the dished portion, the entering edge of said blade being curved to conform tg the shape of-a radial section of said disc,

and the trailing edge being curved similarly greater width along v to provide a blade of its outermost edge.

5. 4In a propeller, the combination of a hub having blades secured .thereto at different 'angles to the axis of said hub, the'width of said blades, measured circumferentially, increasing rapidly from the hub to the outer circum erential edge of same, the portion of said blades adjacent the hub being curved towards the face of said propeller, and said.

has the appearance of an unbroken disc, similar to the disc from which lthe blades originally were cut, as shown in Fig. 4. This apparent formation vis effected by the curved entering edge 15 of the blades on the revolving propeller.Y The effect of such 'a propeller v'since there is no air loss off the ends of the blades tends to maintain lthe stability of a flying machine and cause it to remain in its true course whether horizontally or verti- 

